Insect pheromones can be used in a variety of insect control strategies that include mating disruption and attract-and-kill, as well as mass trapping. These strategies have proven to be effective, selective (e.g., they do not harm beneficial insects, such as bees and lady bugs), and safe (e.g., the compounds are generally biodegradable and do not accumulate in the food chain). Even the very stringent USDA Organic Program lists insect pheromones as one of the few synthetic organic compounds allowed in organic crop production, another important recognition of the high safety of these products. Accordingly, pheromones already form the basis of integrated pest management (IPM) practices in fruit production on the U.S. west coast, and their use in organic farming is growing worldwide.
Despite these advantages, pheromones are not widely used today because of the high cost of about $500 to $14,000 per kg of active ingredient (AI). Even though thousands of insect pheromones have been identified, less than about twenty insect pests worldwide are currently controlled using pheromone strategies, and only 0.05% of global agricultural land employs pheromones.
Lepidopteran pheromones, which are naturally occurring compounds, or identical or substantially similar synthetic compounds, are designated by an unbranched aliphatic chain (between 9 and 18 carbons) ending in an alcohol, aldehyde, or acetate functional group and containing up to 3 double bonds in the aliphatic backbone.
The present invention provides methods by which lepidopteran insect pheromones as well as structurally related compounds are prepared using synthetic strategies that are enabled by a biocatalytic step.